In recent years, hard back entrance rugs or mats have become popular items for use at office locations of commercial and industrial enterprises, and these rugs are normally rented to such enterprises with the rental company being obligated to clean the rugs periodically. Such rugs are generally relatively small (e.g. 3 feet by 5 feet), and they include a backing of cotton-latex or nylon-vinyl to which are secured a variety of pilings, such as polyester, nylon, acrylic, and polypropylene.
The owner of such rugs is faced with the problem of cleaning large quantities of the rugs on a regular basis, and, as explained in greater detail in an article appearing at page 46 of the May, 1975, issue of Industrial Launderer magazine, two general types of cleaning equipment have been available heretofore for cleaning these rugs.
The first type are so-called "dry" machines which provide only mechanical means for vigorously beating the rugs, and which have been found to be unacceptable.
Additionally, "wet" machines are available which include, in various combinations, water and detergent sprays to soak the rug, and a plurality of brushes or mechanical fingers which are pressed against the rug piling to agitate the piling mechanically and loosen the dirt therefrom. While this type of cleaning equipment generally provides satisfactory cleaning results, the severe mechanical agitation of the piling by the brushes has a deleterious effect on the piling fibers, particularly in rugs having flocking secured to the rug backing by an adhesive in a predetermined design as disclosed, for example, in U.S. Pat. No. 3,793,050, issued Feb. 19, 1974, to Mumpower. Moreover, the adverse effects of mechanical agitation also serve to limit substantially the speed at which the rugs can be moved past the brushes, thereby limiting the cleaning cycle time for such rug cleaning equipment.